In the past, registration information items of a plurality of persons have often been registered with a memory and searches have often been made to determine whether or not a person who input information which agrees with the registered registration information item is a registered person, as is the case with a system managing the entry and leaving a predetermined place, for example. In that case, so-called “1:N authentication” is made to verify information-for-authentication for inputting against each of the registration information items registered with the memory.
A device configured to generate a low-resolution transformation registered image and a transformation verification image based on a plurality of registered images and a verification image for authentication, and determine whether or not a registered image which becomes the generation source of an upper prescribed number of transformation registered images showing strong correlations with the transformation verification image is a registered person based on the result of verification against the verification image for authentication has been proposed as an authentication device of that type (refer to Patent Document 1, for example).
Patent Document 1: Japanese Unexamined Patent Application Publication No. 2005-215883
Incidentally, in the authentication device having that configuration, the low-resolution transformation registered image and the transformation verification image are generated each time the verification image for authentication is input (each time the authentication processing is started). Therefore, the authentication processing speed is decreased by as much as the generation.
As an exemplary solution to the problem, it can be considered that the low-resolution transformation registered image is generated each time each of the registered images is registered, and the particular transformation registered image is associated with the registered image and registered with a memory. However, according to the example, a problem of a significantly increased storage capacity arises.